Preparation of rare earth chlorides by chlorination of monazite

Abstract

An investigation has been made of the reaction between monazite, chlorine and either carbon or carbon monoxide. Conditions have been established for obtaining yields up to 90% of relatively pure rare earth chlorides at chlorine efficiencies in excess of 50% The thorium content of monazite is shown to react with chlorine much more slowly than the rare earth elements. The nature of the volatile products of the reaction has been investigated and the mechanism of the reaction discussed.